Concentrator for minerals



Oct. 17, 1967 A. A.JOHNSTON I 3,347,376

CONCENTRATOR FOR MINERALS Filed July 15, 1966 2 SheetsSh eet 1 INVENTOR. ARTHUR A JOHNSTON ATTORNEY Oct. 17, 1967 A. A.JOHNSTON 3,347,376

CONCENTRATOR FOR MINERALS Filed July 15, 196 6 2 Sheets-Sheet 2 INVE NTOR. ARTHUR A. JOHNSTON ATTORNEY United States Patent 3,347,376 CONCENTRATOR FOR MINERALS Arthur A. Johnston, 2417 NE. 39th Ave., Portland, Oreg. 97212 Filed July 15, 1966, Ser. No. 565,613 6 Claims. (Cl. 209-444) The present invention is concerned with the separating out of desired particles of relatively high density, such as gold in particular, from a mass of crushed ore, gravel or sand, the pieces and particles of which have much lower density.

The main object of this invention is to obtain a highly eflicient and rapid separation and concentration of the desired high density particles from the mass of material being processed.

A related object is to obtain such concentration of desired particles without the customary employment of a considerable amount of water, and even without the employment of any water in the process, inasmuch as separating out and obtaining the concentration 'of desired high density particles from the mass of material by the commonly employed hydraulic means, in which a large amount of water is employed, is known to be wasteful since some particles of the desired concentrate invariably will be carried along in any substantial flow of water and thus lost with the waste material.

A further and specific object of the invention is to provide an approved individual separator pan, adapted for use either as a sole separator pan or as one of a plurality of identical separator pans in a mineral concentrator in which each pan operates independently but in parallel with the others in thedevice.

The manner in which these objects are attained, the manner in which the improved separator pan is constructed, and the manner in which such pan functions in a concentrator of the type described will be briefly explained with reference to the accompanying drawings.

In the drawings:

FIG. 1 is a side elevation of a concentrator containing a plurality (for example 6) of identical separtor pans embodying the present invention;

FIG. 2 is a plan section taken on line 2-2 of FIG. 1, drawn to a slightly larger scale, with part of the upper portion of a top distributor pan assembly shown broken away for clarity;

FIG. 3 is a section on line 3-3 of FIG. 1 drawn to a larger scale, being also a top plan view of oneof the individual separator pans in the concentrator, with portions of this pan broken away for clarity;

FIG. 4 is a section taken on the line indicated at 4-4 in FIG. 3, drawn to a still larger 'scale but foreshortened;

FIG. 5 is a fragmentary section on line 5-5 of FIG. 3, drawn to a considerably enlarged scale and showing one of the controllable outlets of the separator pan; and

FIG. 6 is a section on line 6-6 of FIG. 5, being also a section on line 6-6 of FIG. 3 drawn to the same scale as FIG. 5.

Referring first to FIG. 1, the concentrator includes a supporting framework 10 having a rectangular base 11 and a pair of identical A frames 12 and 13, the bottom ends of which are rigidly secured to the base at the four corners of the base respectively, and which frames rigidly support apair of transverse top members, one of which is shown at 14 in this figure. Within this supporting framework is an oscillating rectangular pan-supporting frame 15 composed of a pair of side members 16, 16, a top member 17, and a bottom member 18. The bottom member 18 is rigidly attached to a central inverted dished disc 19 which has a concave bottom flange and which rests on a round bottom member 20 firmly secured to the base of the main frame. A stud shaft 21 extends up- 3,347,376 Patented Oct. 17, 1967 wardly from the center of a top member 17 of this oscillating frame and is received in a bearing recess in a cam arm 22 secured to the bottom of a driven rotating shaft 23 which is rotatively carried in a bearing supported between the pair of top cross members 14 of the stationary main support frame.

The portion of the device as thus far described is similar to the device described in more detail in United States Letters Patent No. 2,822,090, issued on February 4, 1958, entitled Concentrator for Minerals, to which reference should here be made, and the means by which the oscillating pan-supporting frame 15 is given oscillation and measured vibrations are the same as those described in the said patent No. 2,822,090 and need not be described here since these form no part of the present claimed invention.

Secured to the oscillating frame 15 are an annular accumulator pan 24, a plurality (thus 6 as illustrated in FIG. 1) of identical separator pans 25 which are stacked one above the other in axial alignment and a top distributor pan assembly 26. The top distributor pan assembly 26 (see also FIG. 2) has a bottom wall and a side wall, the latter being divided into a lower portion 27 and an upper portion 28, with the upper portion being of greater diameter than the lower portion and thus providing an annular inside ledge 29 between lower and upper portions. A circular screen 30 is removably placed on this ledge 29. A pair of diametrically opposite ears 41, integral with and extending outwardly from the upper wall 28, are secured by suitable screws to the side members 16 respectively of the oscillating frame 15.

Parts of the lower side wall portion 27 of the distributor pan assembly 26 are extended outwardly so as to form, with correspondingly extended portions of the bottom wall, a pair of identical, diametrically opposite arcuate outer distribution chambers 31, 31, each of which chambers is covered with a top wall. The bottom wall in each of these distribution chambers 31 is provided with a plurality of outlet ports 32, one for each of the separator pans 25 located below the distributor pan assembly, and flexible tubes 33 (FIG. 1) lead down from these ports to receiving chambers on the respective separator pans, as presently explained.

Since the separator pans 25 are all identical, it will suffice to describe one of them with reference particularly to FIGS. 3 and 4. The pan 25 has a circular peripheral wall, the upper portion of which is formed with two diametrically opposite inlet or receiving chambers 34 which extend outwardly. These chambers are shaped as shown in FIG. 3 and open into the pan. They have outer side, top and bottom walls. The bottom wall of each chamber is extended inwardly into the pan and forms a triangularly shaped dispensing shelf 35, with a flange 36 extending along the inner edge, whereby material delivered into the chamber from the outside will pass along on the bottom of the chamber and thence onto the inside shelf portion 35 and be discharged over the inner end of the shelf portion. The outside top wall of each of these chambers 34 is provided with an inlet port 37 to which the lower end of a flexible tube 33 (FIG. 1) is connected, the top end of such tube being connected to an outlet port in a distributor chamber 31 of the distribution pan assembly 26 as previously mentioned.

The peripheral wall of the pan 25 terminates at the top in an inwardly extending flange 38, on which is placed a gasket 39 for the purpose of closing the space between such pan 25 and the next pan above it. The pan 25 is provided with a pair of diametrically opposite, outwardly extending ears 40 which are secured by suitable screws to the side members 16 respectively of the oscillating frame 15.

The bottom wall 42 of the pan 25 slopes inwardlyupwardly from the peripheral wall, as shown in FIG. 4, and joins the wall of a central tubular discharging channel 43, which extends up from the bottom wall and terminates at the top in an outwardly extending annular flange 44 positioned a short distance above the surrounding bottom wall of the pan as shown in FIG. 4. This discharging channel 43 extends down below the bottom wall of the pan for a distance sufficient to enable the channel to terminate a short distance above the top flange 44 of the corresponding discharge channel of the next lower pan.

, A first annular baffle 45 (FIGS. 3 and 4) is mounted in the pan 25 beginning a short distance inwardly from the peripheral wall of the pan. This :balflle is supported spaced above the bottom of the pan by a plurality of sleeved screw or bolts 46, the bottom ends of which are secured in the bottom wall. This baffle 45 has an outer downwardly-extending peripheral flange 47 (FIG. 4) which terminates a slight distance above the bottom wall 42 of the pan. This flange 47 serves a two-fold purpose; namely, it provides a restricted passageway downwardlyoutwardly along the bottom wall 42 beneath the baffie, and it provides rigidity for the baffle 45. The top face of this baflle slopes upwardly and inwardly, as shown in FIG. 4, almost to the inner periphery of the baffle and then terminates in a substantially horizontal rim, as shown in FIG. 4-

A second annular bafile 49 is mounted inwardly in the pan 25 beyond the first bafiie 45. This second baflie is also supported by the sleeved bolts 46 through the medium of the extending arms 49', and is spaced above the bottom wall 42 of the pan. The outer periphery of this second batfle 49, with the exception of the arms 49', is spaced inwardly of as well as below the inner periphery of the first baffle 45. This second bafiie, after a brief substantially horizontal portion 54 extends upwardly and inwardly at a greater inclination than baflie 45, and similarly terminates in a substantially horizontal inner rim 51. This inner rim 51 is spaced outwardly from the flange 44 on the top of the central discharge channel 43, as shown in FIG. 3.

The pan 25 also has a pair of diametrically opposite outlet chambers 52 extending outwardly from the lower portion of the peripheral wall. Each outlet chamber has a bottom wall forming an integral extension of the bottom wall of the pan, a pair of vertical side walls 53, the top edges of which preferably slope downwardly-outwardly, and an outer end wall. These outlet chambers are open at the top. The bottom wall of each outlet chamber has an outlet port 54, and a flexible tube 55 (FIGS. 1, 5 and 6) leads from this outlet port to the annular accumulator pan 24 mounted in the bottom of the oscillating frame 15. The passageway from the pan 25 into each of its outlet chambers 52 preferably is controlled by a gate assembly, later described.

From the description given thus far, the manner in which each separator pan functions in separating out the desired fine heavy particles from the rest of the material being processed as oscillatory vibrations are imparted to the pan can now be explained. The mass of material, deposited in the distributor pan assembly 26 (FIGS. 1 and 2), passing through the screen 30, passes into the two distributor chambers 31 and then passes down from the outlet ports 32 through the tubes 33 into the receiving chambers 34 of the separator pan or pans 25 located beneath the distributor pan assembly. The material reaching a receiving chamber 34 passes inwardly into the pan along the dispensing shelf 35 and is discharged over the inner end of the shelf, the oscillatory vibrations imparted to the oscillating frame and thereby to each separator pan in the frame causing the material to enter into the pan and move around in the pan mainly in a general clockwise direction as viewed in FIG. 3. Some of the smaller, high-density particles may immediately find their way down to the annular peripheral channel 56 of the pan. However, most of the material, when deposited on the first bafile 45, will travel inwardly-upwardly on this bafile rather than outwardly-downwardly under the impetus of the oscillatory impulses given to the pan, and, as will be readily understood, those particles having the lowest density will have the greatest tendency to travel inwardly towards the central portion of the pan.

Of the particles discharged over the periphery of the first baffle 45 some of them, being of greater density, will drop down onto the bottom wall 42 of the pan, while those of lighter density will continue their travel inwardly and arrive on the second baffle 49. Here again some separation of the arriving particles takes place, some of those of greater density moving downwardly on the sloping face of the second baffle and in turn dropping onto the bottom wall 42 of the pan, while the remaining particles continue on inwardly, passing over the inner rim of the second baffie 49, then dropping onto the bottom wall 42 of the pan and finally arriving at the flanged top of the central discharging channel 43. When sufiicient accumulation occurs at this central discharging channel 43 these light density particles spill over into the discharging channel as waste material.

Of the particles which drop from the baffles 25 and 49 onto the pan bottom, those of light density will also move inwardly up the inclined surface of the pan bottom, while those of heavier density take the opposite course. Thus a continuous separation of the higher density particles from lower density particles takes place until the lower density material has reached the central discharging channel 43.

Furthermore, as the result of the impetus given by the oscillatory vibration to the material received into the pan, together with the special arrangement of bafiles for intercepting the material, a constant circulation and recirculation of material which has not reached the central discharging channel 43 takes place in the pan, with a continuing separating out of heavier particles and a gradual accumulation of heavier particles nearer and nearer to the peripheral channel 56. Also the heavier particles, on reaching the peripheral channel 56 continue to follow an upwardly and inwardly swirling course around the periphery, with a considerable portion of this material moving upwardly and inwardly over baffie 45, dropping onto the bottom wall 42 and passing again outwardly on the bottom wall through the restricted spacing between the bottom edge of flange 47 of bafile 45 back to the peripheral channel 56. All the agitation and impacts repeatedly received by the material in its course in the pan contribute to an effective separating of the heavier or higher density particles from those having a much lower density, resulting in the collecting of the desired high density particles in the peripheral channel 56. From the peripheral channel 56 the desired particles finally pass into the outlet chambers 52 and thence down into the bottom accumulator pan 24 through the tubes 55.

Preferably, although not necessarily, the passageways from the peripheral channel 56 out into the outlet chambers 52 are provided with adjustable control gate assemblies 57 in order that the rate at which the accumulating desired higher density particles are delivered from the pan may be controlled, or even such delivery temporarily shut off altogether.

Referring to FIGS. 5 and 6, the discharge gate assembly F 57 consists of a plurality of identical slides 58 arranged side by side between a pair of guide plates 59 which extend transversely across the outlet chamber 59. The bottom edges of the guide plates 59 are spaced above the bottom wall of the outlet chamber 52. The top end of each individual slide 58 is turned down over on the slide to form a clamping spring 60 for engaging the outer guide plate 59 and thus act to hold the slide in either open raised position or in lower closed position, to either of which the slide is manually moved.

Referring again to the concentrator illustrated in FIG. 1, the high density particles from the outlet chambers of the separator pans, passing down through the tubes 55, are finally collected in the annular accumulator pan 24 at the bottom of the oscillating frame 15, and are then obtained through a discharge channel 61. Waste material, passing down through the central discharging channels of the separator pans, is discharged into a suitable outlet channel 62 in the bottom of the concentrator.

I claim:

1. In a mineral concentrator of the character described, a separator pan including an outer peripheral wall, a bottom wall having a discharging channel centrally mounted therein, said bottom wall sloping upwardly from said outer peripheral wall to said discharging channel, a receiving chamber mounted on the outside of the upper portion of said peripheral wall and leading into said pan, the bottom wall of said chamber extending into said pan and forming a discharging shelf, an outlet chamber mounted on the outside of the lower portion of said peripheral wall, an annular bafile mounted in said pan spaced above said bottom wall of said pan and extending beneath said shelf, the outer periphery of said baffle spaced inwardly from said peripheral wall of said pan, the top face of said bafile sloping upwardly-inwardly at a greater inclination than said bottom wall of said pan, and the inner periphery of said baffle spaced outwardly from said central discharging channel.

2. The combination set forth in claim 1 with said baffle having a downwardly-extendin g flange on the outer periphcry of said bafile terminating a short distance above said bottom wall of said pan and with said inner periphery of said baffle terminating in a substantially horizontal rim spaced outwardly from said central discharging channel.

3. The combination set forth in claim 1 with the addition of a second annular baflie in said pan spaced above said bottom wall of said pan, said second baffle having an outer periphery spaced inwardly from and below said inner periphery of said first baflle, and the top face of said second bafile sloping upwardly and inwardly and terminating in an inner periphery n'm spaced outwardly from said central discharging channel.

4. The combination set forth in claim 1 with the addition of a second annular baflle in said pan spaced above said bottom wall of said pan, said second bafile having an outer periphery spaced inwardly from and below said inner periphery of said first baffle, the top face of said second baffle sloping upwardly and inwardly at a greater inclination than said top face of said first baflle and terminating in an inner periphery rim at a higher elevation than the inner periphery of said first baffie and spaced outwardly from said central discharge channel.

5. In a mineral concentrator of the character described, a plurality of identical separator pans, each pan including an outer peripheral wall, a bottom wall having a discharging channel centrally mounted therein terminating a short distance above said bottom wall, said bottom wall sloping upwardly from said outer peripheral wall to its intersection with said discharging channel, a pair of diametrically opposite outlet channels mounted on the outoutside of the upper portion of said peripheral wall and leading into the pan, the bottom wall of each chamber extending into the pan and forming a substantially triangular discharging shelf, a wall extending along on said shelf opposite to said peripheral wall, a pair of diametrically opposite outlet channels mounted on the outside of the lower portion of said peripheral wall, a first annular bafile mounted in the pan spaced above said bottom wall of the pan and extending beneath said shelves, the outer periphery of said baffle spaced inwardly from said peripheral wall of the pan, the top face of said baflle sloping upwardly-inwardly at a greater inclination than the bottom wall of the pan, and a second annular baflle in the pan spaced above said bottom wall of the pan, said second baflie having an outer periphery spaced inwardly from and below said inner periphery of said first mentioned bafiie, means for rigidly supporting said first and said second baffles in the pan, the top face of said second baflle sloping upwardly and inwardly at a greater inclination than said top face of said first baffie and terminating in an inner peripheral rim at a higher elevation than the periphery of said first baffle and spaced outwardly from said central discharging channel.

6. The combination set forth in claim 5 with said first bafile having a downwardly-extending flange on the outer periphery of said baffle terminating a short distance above said bottom wall of the pan, with said pair of outlet chambers spaced an arcuate distance on said periphery of said pan from said receiving chambers respectively, and with a gate assembly controlling the passageway into each of said outlet chambers.

References Cited UNITED STATES PATENTS 1,141,972 6/1915 Muhlernan 209-479 X 2,484,203 10/ 1949 Beck 209-446 2,822,090 2/1958 Johnson 209481 HARRY B. THORNTON, Primary Examiner. TIM R. MILES, Examiner. 

1. IN A MINERAL CONCENTRATOR OF THE CHARACTER DESCRIBED, A SEPARATOR PAN INCLUDING AN OUTER PERIPHERAL WALL, A BOTTOM WALL HAVING A DISCHARGING CHANNEL CENTRALLY MOUNTED THEREIN, SAID BOTTOM WALL SLOPING UPWARDLY FROM SAID OUTER PERIPHERAL WALL TO SAID DISCHARGING CHANNEL, A RECEIVING CHAMBER MOUNTED ON THE OUTSIDE OF THE UPPER PORTION OF SAID PERIPHERAL WALL AND LEADING INTO SAID PAN, THE BOTTOM WALL OF SAID CHAMBER EXTENDING INTO SAID PAN AND FORMING A DISCHARGING SHELF, AN OUTLET CHAMBER MOUNTED ON THE OUTSIDE OF THE LOWER PORTION OF SAID PERIPHERAL WALL, AN ANNULAR BAFFLE MOUNTED IN SAID PAN SPACED ABOVE SAID BOTTOM WALL OF SAID PAN AND EXTENDING BENEATH SAID SHELF, THE OUTER PERIPHERY OF SAID BAFFLE SPACED INWARDLY FROM SAID PERIPHERAL WALL OF SAID PAN, THE TOP FACE OF SAID BAFFLE SLOPING UPWARDLY-INWARDLY AT A GREATER INCLINATION THAN SAID BOTTOM WALL OF SAID PAN, AND THE INNER PERIPHERY OF SAID BAFFLE SPACED OUTWARDLY FROM SAID CENTRAL DISCHARGING CHANNEL. 